Glitch while driving: Concerning

[MistaEV]

While driving home today, I had autosteer, autopilot, and traction control all shut off. Automatic emergency braking also shut off and it told me to contact Tesla service. In addition, the car would at times accelerate on its own, even when my foot was off the pedal (from 40-46 and 60-64). This was not on a downhill. Instead, it was on a flat straightaway. Because I was in heavy traffic and on the way to pick up my kids, I drove this way until I got to their daycare. Once there, I powered the car off, powered it back on, and the errors were still present.
After getting the kids packed up from daycare, I got into the car and started it up. It continued to give the errors until about 5 minutes later, when I was underway again. I have not contacted the service center yet as I have no time at this immediate moment to take it in if necessary. Although everything has been restored, I want this to be recorded. With Tesla service.

 

[slipnslider]

I'm sure tesla will say their logs "prove" that it only accelerated when you pressed the pedal. They always say that.

 

[mhan00]

While driving home today, I had autosteer, autopilot, and traction control all shut off. Automatic emergency braking also shut off and it told me to contact Tesla service. In addition, the car would at times accelerate on its own, even when my foot was off the pedal (from 40-46 and 60-64). This was not on a downhill. Instead, it was on a flat straightaway. Because I was in heavy traffic and on the way to pick up my kids, I drove this way until I got to their daycare. Once there, I powered the car off, powered it back on, and the errors were still present.
After getting the kids packed up from daycare, I got into the car and started it up. It continued to give the errors until about 5 minutes later, when I was underway again. I have not contacted the service center yet as I have no time at this immediate moment to take it in if necessary. Although everything has been restored, I want this to be recorded. With Tesla service.

Could be regen kicking on and off. My Leaf and Volt would have the regen kick off after going over a bump while regen braking and it would feel like the car surged forward, and that’s with a weaker regen profile than the one Tesla uses (my Leaf was an old one that didn’t have the B driving profile with more aggressive regen). If your car is throwing errors like that, maybe something like that is happening.

 

[sundaymorning]

While driving home today, I had autosteer, autopilot, and traction control all shut off. Automatic emergency braking also shut off and it told me to contact Tesla service. In addition, the car would at times accelerate on its own, even when my foot was off the pedal (from 40-46 and 60-64). This was not on a downhill. Instead, it was on a flat straightaway. Because I was in heavy traffic and on the way to pick up my kids, I drove this way until I got to their daycare. Once there, I powered the car off, powered it back on, and the errors were still present.
After getting the kids packed up from daycare, I got into the car and started it up. It continued to give the errors until about 5 minutes later, when I was underway again. I have not contacted the service center yet as I have no time at this immediate moment to take it in if necessary. Although everything has been restored, I want this to be recorded. With Tesla service.

Get it in service. No one here will be able to diagnose it.

 

[Frank88]

I can diagnose it.
It's unsafe.

 

[MistaEV]

Get it in service. No one here will be able to diagnose it.

I wasn't asking for a diagnosis, lol. I was just posting something I experienced. I even said that I would report it to Tesla service...

 

[MistaEV]

Could be regen kicking on and off. My Leaf and Volt would have the regen kick off after going over a bump while regen braking and it would feel like the car surged forward, and that’s with a weaker regen profile than the one Tesla uses (my Leaf was an old one that didn’t have the B driving profile with more aggressive regen). If your car is throwing errors like that, maybe something like that is happening.

I'm not sure that it is related to regen braking. The car never slowed or braked, it would only increase speed. Actually at least one of those times it was more like a slight surge in speed, 3-5 mph increase, whereas the other times it was a 1 mph increase until I applied the brake.

In any event, I will update this post when I get it in the service center.

 

[hacer]

I'm not sure that it is related to regen braking. The car never slowed or braked, it would only increase speed. Actually at least one of those times it was more like a slight surge in speed, 3-5 mph increase, whereas the other times it was a 1 mph increase until I applied the brake.

In any event, I will update this post when I get it in the service center.

So TACC was working then? Because otherwise if the car "never slowed or braked" that would require neutral or a foot on the throttle pedal.
I think that TACC is usually disabled when traction control is disabled. With all of those other warnings, and especially with an actual unexpected "surge in speed," I would have for sure disable TACC for the rest of the drive. Why didn't you?

 

[MistaEV]

So TACC was working then? Because otherwise if the car "never slowed or braked" that would require neutral or a foot on the throttle pedal.
I think that TACC is usually disabled when traction control is disabled. With all of those other warnings, and especially with an actual unexpected "surge in speed," I would have for sure disable TACC for the rest of the drive. Why didn't you?

I'm a bit confused by your questions. First, let me clarify one point; the car never slowed or braked on its own. I had to apply the brake myself. TACC was not working. I could not access ANY features related to driving and EA. I did not have any of the features enabled because every feature turned itself off and I would see a message flash on the screen that said "Autosteer disabled", "Automatic Emergency Braking Disabled", "Autopilot Disabled". Prior to losing my EA, my autopilot speed was set to 65 and when I took my exit, I applied the brakes. This would have turned off cruise control (if it was even on; it was not. I lost my cruise control as soon as my EA failed) and I even allowed my speed to drop to 20 on the exit ramp to see what would happen, although I could have maintained my speed through the curves naturally.

When I left the exit ramp and turned onto one of the main roads, the speed was at 40; this increased on its own to 46, 1 mile at a time. I braked, and the car behaved normally. On the second main road, I had the car traveling at 40 again and it started to creep upwards, at 3-5 miles a click/tick. This was without any input from me, pressing the accelerator. I applied the brakes when it hit 52. So again, TACC was not working AT ALL nor was it on AT ALL.

 

[morrisdl]

I had the same slow acceleration a couple weeks ago: https://photos.app.goo.gl/dTVUCqanUtjjExs97
on 2018.10 with AP1 on a two lane road in Mesa Verde Nat Park. It accelerated past the TACC setting and the typical +5mph limit. Did it twice that morning, but never since. Support said the accelerator was depressed, but I can confirm it was not by my foot.

 

[hacer]

I'm a bit confused by your questions. First, let me clarify one point; the car never slowed or braked on its own. I had to apply the brake myself. TACC was not working. I could not access ANY features related to driving and EA. I did not have any of the features enabled because every feature turned itself off and I would see a message flash on the screen that said "Autosteer disabled", "Automatic Emergency Braking Disabled", "Autopilot Disabled". Prior to losing my EA, my autopilot speed was set to 65 and when I took my exit, I applied the brakes. This would have turned off cruise control (if it was even on; it was not. I lost my cruise control as soon as my EA failed) and I even allowed my speed to drop to 20 on the exit ramp to see what would happen, although I could have maintained my speed through the curves naturally.

When I left the exit ramp and turned onto one of the main roads, the speed was at 40; this increased on its own to 46, 1 mile at a time. I braked, and the car behaved normally. On the second main road, I had the car traveling at 40 again and it started to creep upwards, at 3-5 miles a click/tick. This was without any input from me, pressing the accelerator. I applied the brakes when it hit 52. So again, TACC was not working AT ALL nor was it on AT ALL.

Ok, so TACC was disabled and with no foot on either pedal the car was not "slowing or braking" Do I have that right? Because that would mean, at a minimum, that there was no regen (which is abnormal with no pressure on the throttle).

I'm not sure that it is related to regen braking. The car never slowed or braked, it would only increase speed. Actually at least one of those times it was more like a slight surge in speed, 3-5 mph increase, whereas the other times it was a 1 mph increase until I applied the brake.

It is this quote I'm wondering about, that it didn't slow or brake with no foot on any pedals. That says to me there was also a problem with regen, because the car should certainly have been slowing but it wasn't. I don't think the absence of regen can explain the periods of acceleration (as @mhan00 suggested) because it was missing entirely in the first place! So you did have a big problem with regen: there was none. So that's another thing to add to the long list of problems. Did the energy display show no regen, and the dashed lines associated with not being able to regen?

 

[jamnmon66]

Mine had almost exactly the same symptoms the other day. I drove it home & tried a reset. No change. I called Tesla. They said that they couldn't diagnose it remotely and dispatched a tow. When the driver called, I went out to turn the car around so that the front was facing the street and all of the errors were gone. I called back and they said nothing was showing on their end. I decided to keep it but I left town the next day. I'll be home on Monday night so we'll see if there are any other issues.

 

[MistaEV]

Ok, so TACC was disabled and with no foot on either pedal the car was not "slowing or braking" Do I have that right? Because that would mean, at a minimum, that there was no regen (which is abnormal with no pressure on the throttle).
It is this quote I'm wondering about, that it didn't slow or brake with no foot on any pedals. That says to me there was also a problem with regen, because the car should certainly have been slowing but it wasn't. I don't think the absence of regen can explain the periods of acceleration (as @mhan00 suggested) because it was missing entirely in the first place! So you did have a big problem with regen: there was none. So that's another thing to add to the long list of problems. Did the energy display show no regen, and the dashed lines associated with not being able to regen?

Correct, there was no regen. Until you asked this question, I had not thought of it but I do recall checking to see if I was getting regen during the times it was not accelerating and my foot was not on any of the pedals; it did not indicate any regen at all.

On a possibly unrelated note; when TACC is working, taking my foot off the brake in heavy traffic or traffic in general, would usually cause the car to abruptly slow down, if there were a car in front of me. However, when I did this while TACC wasn't working, it slowed like an ICE car, that is, during the times it did not accelerate on its own, it would gradually decrease its speed but there was no feel or sense that the car was auto braking.

 

[diamond.g]

Could a messed up wheel speed sensor cause these errors?

 

[tmwilkin]

While driving home today, I had autosteer, autopilot, and traction control all shut off. Automatic emergency braking also shut off and it told me to contact Tesla service. In addition, the car would at times accelerate on its own, even when my foot was off the pedal (from 40-46 and 60-64). This was not on a downhill. Instead, it was on a flat straightaway. Because I was in heavy traffic and on the way to pick up my kids, I drove this way until I got to their daycare. Once there, I powered the car off, powered it back on, and the errors were still present.
After getting the kids packed up from daycare, I got into the car and started it up. It continued to give the errors until about 5 minutes later, when I was underway again. I have not contacted the service center yet as I have no time at this immediate moment to take it in if necessary. Although everything has been restored, I want this to be recorded. With Tesla service.

I had a similar behavior a few weeks back. My wife had kids for a few hours, so I pulled over and called Tesla. They were on it quickly and asked if they could pick me up. 50 minutes later I was in a loaner S. That said it appears when the Model 3 finds a fault it put itself in "run home to momma mode" and disables all of those connected systems (Regen braking, autosteer, cruise etc which behaves exactly as you describe it. One of their regional techs was in the facility at the time I dropped of the vehicle and he asked me "did it feel like the car accelerates when you left off the gas?" Of which I described yes...he said its not accelerating but the car is so aero that lack of decel feels that way and if you have any carried mass or downhill grade it can accelerate still a bit. When regen is 100% off driving the car feels very abrupt. Anyway FWTW

I should note since I called Tesla immediately they found the fault logs while I was in the car with the issue and the events right prior so that may have helped but I got the indication later that my problem took a bit of post analysis to really nail down the issue and they very apologetically let me know that may in fact take some time. YMMV

 

[morrisdl]

Good point! Mine happened where there was no LTE service for days so that was not possible. My wife insisted that our car was unhappy about being disconnected from the "momma-computer" for so long.

 

[MistaEV]

I had a similar behavior a few weeks back. My wife had kids for a few hours, so I pulled over and called Tesla. They were on it quickly and asked if they could pick me up. 50 minutes later I was in a loaner S. That said it appears when the Model 3 finds a fault it put itself in "run home to momma mode" and disables all of those connected systems (Regen braking, autosteer, cruise etc which behaves exactly as you describe it. One of their regional techs was in the facility at the time I dropped of the vehicle and he asked me "did it feel like the car accelerates when you left off the gas?" Of which I described yes...he said its not accelerating but the car is so aero that lack of decel feels that way and if you have any carried mass or downhill grade it can accelerate still a bit. When regen is 100% off driving the car feels very abrupt. Anyway FWTW

I should note since I called Tesla immediately they found the fault logs while I was in the car with the issue and the events right prior so that may have helped but I got the indication later that my problem took a bit of post analysis to really nail down the issue and they very apologetically let me know that may in fact take some time. YMMV

Thank you! I will call immediately next time I have an issue, because I was not aware of the post log issue. It is reasonable to consider that the logs would only last so long before they were overwritten.

 

[MistaEV]

Good point! Mine happened where there was no LTE service for days so that was not possible. My wife insisted that our car was unhappy about being disconnected from the "momma-computer" for so long.

Come to think of it, that area of I95 has issues with cell signal from time to time. While I am not saying it is or isn't related, it is certainly something I will note next time (if there is a next time; I hope there isn't).

 

[sperkin]

This is a known issue and it's supposed to be fixed in firmware 2018.24.

 

[MistaEV]

This is a known issue and it's supposed to be fixed in firmware 2018.24.

You da person! Thanks for this post.